Solar Energy, Electric Systems
Scientific Policy, Objectives
The scientific activity of team « Supervision, Énergie solaire, Systèmes Électriques Supervision » (Solar Energy, Electric Systems) is dedicated to the study, characterization, modeling, management and supervision of electric systems that mainly include renewable energies sources. Systems that use or couple photovoltaic sources (PV), concentrator photovoltaics (CPV) and thermal solar with other sources are the core of our study.
Theme 1 : Electric Modeling and Characterization of Components for Solar Use
Theme 2 : Electric Systems Management
Sub-theme1 : Embedded Electronic Systems
Sub-theme 2 : Power Electronics
Sub-theme 3 : Distributed Command Architecture
Sub-theme 4 : Smart Grid
Thierry TALBERT, MdC UPVD, Team leader
Emilien DUVERGER (since 2015)
Theme 1 : Electric Modeling and Characterization of Components for Solar Use – Olivier Fruchier and Dorian Gachon
An electric system is at least composed of the following units: one/some source(s) (PV,CPV, wind-powered, fuel cell), one/some conversion system(s) of electrical energy (chopper, power inverter), one/some storage system(s) (battery, H2) and one/some command and supervision system(s). Evolution of semiconductors electronics leads to model and characterize the new components (switches, PV cells, etc.) when they are subjected to particular functioning constraints. In the photovoltaic field, technological evolutions of PV and CPV cells need the manufacturing of new semiconductor components, particularly switches and associated commands. These elements need to be to characterized, but also electrically modeled.
- Electric modeling low frequencies (parameters Z and H) and high frequencies (parameters S). The manufacturing of new switches, in this case of high-power GaN transistors (interaction with team ISGE of the LAAS), requires the electric characterization and development of the corresponding models in low and high frequencies. This models will be used in theme Electric Systems Management/Power Electronics and Electric Systems Management/Distributed Command Architecture.
- Electromagnetic modeling for the study of conductive or radiative EMC. The development of a distributed command architecture requires to know the electrical interactions between the different elements that form the circuit (passive components, switches and circuitry). The study of the electric signature, current harmonics that are conductive and radiative in the electric network, will enables the set up of an EMC model. This model will be used for the set up of a distributed command, among other things, of the converters command DC/DC (Electric Systems Management/Power Electronics/Distributed Command Architecture).
- Tools : test benches of electric characterization I(V) and C(V) in low and high frequencies
Theme 2 : Electric Systems Management
Sources made of PV cells, just like windmills, are highly inconsistent and not easily predictable resources. Integrate them in an electric system as the main source or in addition, requires the development of new conversion and management electric structures, if we want to minimize, or even get rid of storage elements. These new elements implement researches in the following fields :
- Embedded: for the realization, among other things, of communicating smart-sensors;
- Power electronics: for the realization of new architectures that maximize the relation weight/power of electric conversion systems;
- Command: of which architecture needs to be distributed because of the growth of electric converters that are more and more numerous on networks including renewable energies, that have functioning processes interfering more and more between each other.
To all these researches, we have to add electric signatures of the defects and the supervisor realization to reach an optimal functioning of electric energy used in an autonomous system and/or an intelligent electric system.
Sub-theme1 : Embedded Electronic Systems – Dorian Gachon
Team SenSe makes embedded electronic systems for the design of smart-sensors (tension current measurement for PV and smart-grid installations, of environmental systems, etc.), sensors for applications in strict outputs and hostile environments (collaboration with Frec|n|sys, the only French foundry of sieve SAW and RF-MEMS components, resonators and sensors), low energy communication systems (LoRa, SigFox) and chip-command systems (PIC, AVM, ARM, FGPA) and integration of the specific command with the corresponding language (C, VHDL).
Measurement systems in real time are currently used for the measurement of energy consumption of the Wallon building from project Rivesaltes-Grid in collaboration with La Compagnie du Vent (Engie group, Fig. 3).
Sub-theme 2 : Power Electronics – Thierry Talbert
Team SenSe makes development of electric energy conversion architectures (buck choppers, boost, sepic, multilevels…) for the realization direct tension bus for energy production systems (ex: PV and CPV, Fig. 6, Fig. 7) and development of architectures (specific power and command) for batteries charge/discharge systems (Fig. 5).
Sub-theme 3 : Distributed Command Architecture – Frederik Thiery
The parallelization of static converters, particularly in the case of structures as 1 converter/1 PV panel/1 CPV cell leads to flickering problems. The developed solution is a software solution, based on a new command architecture using the principle of the command, distributed to all the converters. The commands of the converters are no longer synchronized but desynchronized. These desynchronizations (or injection of desynchronized commands) are managed by a supervisor (Fig. 8). The developed distributed architectures are used in the theme Smart Grid.
- The studied smart-grid by SEnSE team is a micro-grid or block composed of renewable energies sources, storage and EMS (Energy Management Systems). The purpose is to optimize energy exchange between the previous blocs adding electrical fault detection of the grid. Our team is currently working on a 60kW micro-grid in Rivesaltes, made of PV, storage (80kW), an electric vehicle and building in self-consumption. The techniques we use consist in reducing the power requested on the distribution network in case of need and increasing the electricity production using renewable means, and still creating value. The theme will appeal in particular self-consumption possibilities and load transfer. The ongoing project is made with La Compagnie du Vent (Engie Group).
Device : Resource prediction using satellite images
Estimation approach of instant solar irradiation from images of the visible channel of METEOSAT: GISTEL method. Optimized method with the integration of infra-red images in a blurred interferences system. This last stage, in addition with the cloud tracking device enables the prediction of the global solar irradiation on short term (h+12, Fig. 9, Fig. 10).